Material design of Al/CFRP hybrid composites for the hull of autonomous underwater vehicle

The AUV(Autonomous surface vehicle) is widely used for military purpose and scientific purpose. The AUV can save human life from severe environment and reduce the operating cost of underwater equipment. Generally, hulls of AUV are made of composite materials or metal alloys such as aluminum alloy and titanium alloy. Composite materials are well known as its light weight, corrosion resistance and freedom of shape design. But, composite materials are not have plastic deformation so this can be a disadvantage as the materials for underwater equipment. From this reason, this study focused on the reliability of the material. This study contains material design, experiment for materials and verification by FEA. The material what was focused on this study is Al-CFRP hybrid composites. There are used two kinds of Al-CFRP hybrid composites. Inter laminar property between Aluminum alloy and carbon fiber reinforced composites is very important. So, two kinds of Al-CFRP were used for this study. One is co-cured material and the other is post-bonded. Tensile and interlaminar test were achieved to define material properties. Profits from use of Al-CFRP sandwich material are like these. First, this material can enhance the buckling performance and second, it can achieve the reliability against failure at a moment. Mechanical tests are achieved for designed materials and its results are used for FEA. This study verify the feasibility about Al-CFRP hybrid composites for AUVs. The hull of AUV manufacturing and ocean diving test will be achieved in future work.